Diagnostic bite stick



FIG. 1 is a top plan view of a diagnostic bite stick showing my new design;

FIG. 2 is a front elevational view thereof, the undisclosed rear being a mirror image;

FIG. 3 is a bottom plan view thereof; and,

FIG. 4 is a left end elevational view thereof. 

The ornamental design for a diagnostic bite stick, as shown. 